Temperature regulator



Sept, 1942. L M PUSTER f 2,295,427'

TEMPERATURE REGULATOR Filed July l2, 1940 2 ShStS-Shet l lllllllllli @R33 m O U' l vr54? 159i 66 :i l 67 1 66. 75 l 64 Z5 @1 yq K 66 6 `63 76 72 1 Unven'or ma* "51 lm 9a.@m.

Caml/Lon, Mowws SBP@ 8, 1942- L. M. PusTER TEMPERATURE REGULATOR Filed July 12, 1940 Sheets-Sheet 2 vum Q2u@ MQW.

Patented Sept.' 8, 1942 2,295,427 TEMPERATURE'V REGULATOR Louis M. Puster, Knoxville, Tenn., assigner to The Fulton Sylphon Company,

Knoxville. Tenn.. a

corporation of Delaware Application July 12, 1940, Serial No. 345,223

19` calins. (ci. zas-99) This invention relates to temperature regulators and, more particularly, to temperature regulators of the type which employ meansfor co'mpensating for fluctuations in temperature other than that to which the temperature regulator is intended to respond for performing its designed function.

As will be apparent to those skilled in the art from the description of the invention hereinafter contained, said invention can be embodied in temperature regulators of a wide variety of form and construction ,and applied to a wide variety of uses, but for purposes of exemplifying the invention it will be illustrated and described as embodied in an oven regulator, the invention being of particular utility when applied to this use.

An oven regulator is designed to respond to variations in the temperature within the oven and control the medium supplying heat to the oven, whether electric, gaseous or liquid fuel, etc., to the end that a predetermined temperature may be maintained as nearly as may be within the oven. As thethermostatically operated switch, lvalve, or whatnot is ordinarily closely associated with the `stove or other instrumentality containing the oven, the temperature of the ambient surrounding the thermostatic system will obviously vary from a variety of causes,

as the number of burners that may be lighted 3 if the oven is associated with a stove having.

burners for other purposes than heatingthe oven, or the temperature of the room, the presence or absence of drafts, etc. Again, in the case of thermostatically controlled gas valves,

the temperature of the gas itself will vary, de-

pending upon Whether it is flowing from pipes in relatively cold ground as in winter or from pipes whose temperature has been raised by summer heat, and these temperature variations may be communicated to the thermostatic system. 'I'hese and other sources of temperature fluctuation at or around the thermostatic system by which the heating medium is controlled are productive of variations in the expansion or contraction of the thermostat itself and the associated metal parts which do not reflect variations of temperature in the oven to which, ideally, the thermostatic system should alone respond.

In recognition of the foregoing difdculties in providing a thermostatic system that will control the heating medium closely in conformity with the temperature within the oven, numerous proposals have heretofore been made to emthese extraneous sources of temperature variation to the end that the net result of the cooperation of the principal thermostat and the compensating thermostat shall be approximately that which would exist if the thermostatic system responded `only to the temperature within the oven. Devices of this character as heretofore proposed, however, have not been entirely satisfactory because they have generally been of a character which greatly complicated the thermostatic system, materially increasing the number of parts and therefore the cost of production and maintenance, or else they have been of a character which has rendered them only crudely or sluggishly responsive to the extraneous sources of temperature.

It is an object of this invention to provide a thermostatic system of the type referred to wherein the compensating thermostat is simple in construction, and therefore adds little to the complexity of the structure or the cost of production and maintenance, while at the same time it is sensitively responsive to fluctuations of extraneous temperature so that close control of the heating medium may be effected.

In devices of the type under consideration, means `must ordinarily be provided whereby, when the controlling means as a switch or valve is moved4 to extreme position, a continued vchange l 0 of temperature that would otherwise tend to continue the movement of the controlling means in the same direction will not cause injury to the thermostatic system. Thus when the valve member is moved into engagement. with its seat to discontinue the iiow of gas, to take a specific illustration, the temperature at the thermostat may for a period continue to rise, tending to expand the thermostat to a greater extent, but as the valve is abutted against its valve seat such continued expansion may produce enormous bursting pressures within a fluid-type thermostat if no provision is made to permit overrun of the thermostat. Provisions for taking care of this overrun asheretofore employed have also complicated -the construction and added to its cost of production and maintenance.

It is an object of this invention to provide ploy a compensating thermostat responsive .to l5 foregoing functions, whereby the simplicity of the structure is greatly increased with the concomitant advantage of lower production and maintenance costs and less consumption of space.

`A further object of this invention is to provide a device of the type last characterized which is sensitive in its performance of both of these functions.

Another object of this invention is to provide a device of the type heretofore described which is relatively simple in construction, compact, highly efficient, and capable of large scale production at relatively low cost.

Other objects will appear as the description of the invention proceeds.

The invention is capable of receiving a variety of mechanical expressions, three of which are illustrated on the accompanying drawings, but it is to be expressly understood that the drawings are for purposes of illustration only, and are not intended as L. definition of the invention, reference being had to the appended claims for that purpose.

Referring in detail to the accompanying drawings, wherein the same reference characters are employed to designate corresponding parts in the several figures:

Fig. l is an axial section of an embodiment of the present invention;

Fig. 2 is an axial section of another embodiment of the present invention; and

Fig. 3 is an axial section of yet another embodiment of the present invention.

In the form shown in Fig. 1, wherein the invention is illustrated as employed in the control of a gas valve, although it is to be expressly understood that the invention may be embodied in a thermostatically operated switch or a valve for the control of other heating media, the valve casing I0, which may be of any suitable size, construction and material, preferably takes the form of a cup-shaped element -that may be conf venientlyl formed as a sheet metal stamping. Casing I8 is provided with a suitable inlet nipple II and a suitable outlet nipple I2, both illustrated as interiorly threaded for the attachment of suitable piping and retained in apertures in the casing wall in any suitable way as by brazing or soldering. As illustrated, the attachment of the inlet nipple II to the casing I is also employed as a means for retaining in able material.

demands of the installation. As shown.\the valve member 20 is provided with a centrally arranged projecting boss 2I which constitutes a centering means for a coil spring22 which reacts between the face of the valve member .20 and the bottom of the valve seat element I3 andtends to move the valve member toward open position. Valve member 20 at its rear face is made in the form of ashallow cup by provision of the rim 23, and sprung into the shallow recess or depression thus formed is a spider-like resilient element 24 of a dissimilar metal from that of the valve member 20, for a purpose hereinafter explained more in detail. Y

Member 24 is attached in any suitable way, as by a screw 25, to the rigid end member 21 of a thermostatic expansible and collapsible chamber 28 of any suitable size and construction. As

here shown, the peripheral wall of said thermo' static chamber is formed by a corrugated bellows-like element having any suitable slzeand number of corrugations and formed of any suit- As illustrated, said element is composed of two -outwardly extending corrugations and one inwardly extending corrugation, 'and the outwardly extended corrugations are preferably given a loop-like form as illustrated at 29 so that the lateral walls of the corrugations are in engagement when the chamber 28 is in its collapsed condition. Thereby its interior volume is materially decreased and the quantity of thermostatic fluid required to charge the thermostatic chamber is correspondingly diminished. For the same reasons the end member 21 and the opposite rigid end member 38 are preferably extended interiorly of the chamber 28 so as to nearly iffnot quite contact when the chamber 28 is in its collapsed condition, and thereby said chamber is further reduced in interior volume. If desired, the interior volume of the chamber may be still further decreased by providing solid rings at the bends of the outwardly extending corrugations so as to occupy a substantial part of the space thereat without interfering with the designed expansion and contraction of the bellows-like wall. Extending through the end member 30 and communicating with the chamber 28 is a tube or position a valve seat member I3, shown as a Y cup-shaped element clamped to the casing wall by the inwardly projecting end of the nipple II and provided with a suitable seating surface Il at its inner periphery. Valve seat element I3 may also be conveniently formed as a sheet metal stamping.

The wall of the element I3 is provided with an aperture I5 with which co-operates a threaded adjustment plug I6 for varying the eective size of the aperture I5 and thereby controls the minimum flame adjustment. Plug I6 is threadthe control of gas flow in accordance with the 75 pipe 3l suitably sealed into an aperture in the end member 30. Said tube may be wound one or more times around the end member 38 as illustrated, and then it is extended through a threaded gland element 32 hermetically sealed into an aperture in the wall of the casing III and itself forming a hermetic seal with the tube 3|. Tube 3| extends exteriorly of the casing I0 for any suitable length Aand at its outer end comy municates with a bulb 33 of any suitable size and construction and which is designed to be mounted in any suitable way where it responds to the controlling temperature, as the temperature within an oven.

End member 30 is provided with a rearwardly extending stem 34 which is received within the recess 35 of a. sleeve 38 mounted in any suitable way in the end wall 31 of a closure member 38 that is exteriorly threaded for reception within the interiorly threaded open end of the casing I0. a suitable packing 39 being provided to assure a gas-tight joint between the casing III 'and its closure member 38. Mounted on the sleeve 38,

. and securedthereto by set screw 4I, is a rotatable knob I0 for operating the threaded closure member 38. Rotationof the knob 40 causes closure member 38 to move into or out of the action of the spring 28 contracts, by reason of the aperture .in casing I8 whereby thermostatic chamber 28 with its associated valve member 28,

carried thereby may be made to approach the valve seat I4, against Ithe tension of the spring 22, or recede from the valve seat I4 under the 22. Knob 48 has associated therewith any suitable dial and pointer so that the location oi' the its seat may be manually adjusted to maintain that valve setting which corresponds with the temperature that is indicated by the setting oi' the knob 48. A screw 42 in the threaded bore of sleeve 38 enables the location of the stem 3,4, and the thermostatic chamber 28 with its' associated valve member adjustment with respect to the closure member 38I and the knob 48 carried thereby.

I'he thermostat composed of bulb 33, tube 3|. and thermostatic chamlr 28 is charged with any suitable thermostatic material, the charge pref- I4, to receive a factory valve member with respect to erably being a liquidthat completely fills said elements so that the thermostat operates on the liquid expansion principle,

l the resilient member 24 are made of dissimilar metals so selected with respect to their size and the character and extent of extraneous temperasaid liquid being .so selected as to maintain its liquidity and effect the tures for which compensation is to be effected that they co-operate to constitute a bimetallic thermostat that will introduce into the connection between the thermostat proper and the valve member the compensating function heretofore referred to. Furthermore, the resilient member provision that absorbs the overrun movement or the thermostat. By making the valve 28 of aluminum and the member 24 of spring steel, experience has demonstrated that substantially the desired compensation may the same time the member 24 functions as a spring that takes care of any overrun of the thermostat 'if the temperature at the bulb 33l continues to rise after the valve member 28 has engaged its seat i4. However, it is to be expressly understood that other suitable metals may be used for the valve member 28 and other suitable metals may be used for the spring-like member 24 to the end that the combined functions of a compensating thermostat and a provision for absorbing overrun may thus be incorporated be introduced and at into a single structure interposed between the Y In operation,- the heating medium, as gas, en-

ters the casing ii and flows outwardly to the burner through the outlet i2, the quantity of flow, except for the minimum flame provision Aat l5, I6, being determined by the position of the valve member A2li with'respect toits seat I 4. Valve member 28 is moved toward its seat I4 by the expansion of the .chamber 28 underI the expansion of its liquid charge as determinedby the temperature at the bulb 33, while valve member 28 moves away from its seat le, as chamber action of the spring 22. If no other temperature were effective, the valve member 28 would accordingly at all times be so related to itsA seat I4 as would be determined solely by the temperature at bulb 33, and

.its peripheral t with a threaded aperture in the ambient the thermostat and the metallic yparts of the ther-I `so as to produce movements oi' out, iiuctuations oi mostatic system the valve member which are uncalled for by the conditions existing at the bulb 33. Fluctuations in the temperature oi' the heating medium itself may also produce like results. But in conformity with the present invention such iiuctuations oi' temperature in or around the casing il are imparted to the valve member 28 and its associated resilient member 24 of dissimilar metal so that the two, by reason of their co-operation, function as a well known type of bimetallic thermostat dueto the differential expansion of 'the metals employ member 24 flattening or b'owing as diameter is varied by reason of the condition of expansion or contraction of the peripheral wall of the recess or depression in the valve member 28. 'I'hereby the distance between the thermostatic chamber 28 and the valve member 28 is changed and the valve member-itself is repositioned with respect to its seat by an amount that, by proper design of the valve member 28 and .its stantially or precisely compensate for the undesired movement otherwise introduced by the temperature changes around or inside of the casing i8.

thermostat. As soon as the thermostatic chamber 28 begins to contract, the member 24 will return to its normal position by reason of its inherent resiliency and thereafter member 24 will continue to function as one element of thebimetallic thermostat heretofore referred to.

The embodiment of Fig. 2 in many respects resembles that of Fig.' 1 except that in this embodiment the manual adjusting means and the thermostat are disposed on opposite sides of the valve, adjustment being effected by movement of the valve seat with respect to the valve member. As here shown, the casing 58, which may take the form of a casting, or be formed of sheet metal as in the embodiment of Fig. l, is provided with an inlet 5i and an outlet 52 shown as threaded to receive suitable conduits for the gas, or other heating medium. Interiorly, casing 58 is provided between the inlet and outlet referred to 53 in which is received an exterior1y threaded cup-shaped valve seat member 54 providing a valve seat .55 and having one or more apertures 56 in its bottom wall. Cooperating with the valve seat 55 is a valve member'51 which is or may be of the same construction as employed in the kembodiment of Fig. l. Interposed between said valve member ,51 and the bottom of the cup 54 is a -coilspring 58 tending to urge the valve member away from its seat.

Co-operating with the valve member 51, as in the embodimentof Fig. 1, is a resilient spider-like may tend to act on the charge inassociated member 24, will sublits seat by the expansion member I! sprung into the recess or depression at the rear of the valve member l1land constituting a bimetallic compensating thermostat therewith as heretofore explained and also, by reason of the resiliency of the member providing for overrun of the thermostat as heretofore described. Member 59 is mounted in any suitable way upon the end wall 8l of 4an expansible and collapsible chamber 6I whose peripheral wall is formed by a corrugated bellows-like element and whose opposite end is closed by the rigid end wall Il through which extends a tube M leading to any suitable bulb, such as indicated at in Fig. 1,'the thermostat of this embodiment being shown as of substantially the same construction as that illustrated in Fig. 1 and described in more detail hereinabove. Said thermostatic vessel il is shown as clamped by means of the nut BI on the threaded boss 6l projecting from the end member 83 through an aperture 61 in a removable cover plate ll threadedly received in the open end of the. casing l, any suitable provision being made for eilecting a hermetically sealed joint between said cover plate and said casing. Any suitable provision for maintaining a minimum name is provided, a by-pass e .l being shown around the valve seat member il and controlled by a threaded plug 1li having a ker! for adjustment at 1l and a suitable packing gland at 12.

In this embodiment adjustment of the valve is eilected by rotating the valveseat member Il so that, by reason of its threaded engagement with the aperture in the casing 50 the valve seat i5 will be caused to approach toward or recede from the valve member 51. Any suitable means extending to the exterior of the casing 5l for rotating the valve seat member Il may be employed. As here shown, .a stem 13 is connected with the bottom of the valve seat member 5I in any suitable way so as to prevent relative rotation therebetween, and said stem 13 extends through an aperture in the wall of the casing 5l to an exteriorly projecting portion 1l on whichis mounted a sleeve 1B carrying a knob on stem 15 as by a set screw 18 and knob 11 is suitably retained against rotation relatively to the sleeve 1l as by a spring key 1l. Stem 1I interiorly of the casing il has a conical portion Il which is normally urged into fluid-tight engagement with a conical seat at the aperture 1| by a coil spring Il which reacts between the sleeve 1l and the exterior wall of the casing Il or a suitable washer mounted thereon. As in the embodi ment of Fig. 1, knob 11 is provided with anyV suitable indicia so that by co-operation with a pointer the desired temperature setting oi the device may be effected.

` Rotation of the knob 11 advances or withdraws the valve seat Il relatively to the valve member 51, and coil the valve member l1 away from Il. For any given setting of the valve seat member M valve member 51 is advanced toward of the thermostatic chamber li or withdrawn from said seat as said thermostatic chamber 3i contracts by thel action of the spring il. Thereby the ilow o! gas past the valve seat 8l is exactly determined by the position of the valve member l1 with respect to its seat, and the position of said valve member inturn vis determined by the action of the thermostat including the expansible and collapsible chamber il. As in the embodiment of Fig. l, the valve member l1 and resilient member 5l.

1,1. Sleeve 10 is suitably retained the tube 84 extends any suitable way are subjected which would otherwise tend to upset the precise and desired action derived from the relatively remote bulb of the thermostat. i. e., nuctuations of temperature in the ambient surrounding the easing lll, iluctuations of temperature in the medium ilowing through the casing Bil, etc. Said temperatures are imparted to the members l1 and 59 and, by their designed action, they act as a bimetallic thermostat to compensate for such local temperature variations. Ii.' the thermostat tends to expandiafter valve member 51 hasengaged its seat 55, such expansion is absorbed in the deilection of the member 59, against its inherent resiliency, thereby preventing any injury to the parts of the thermostatic system, and when the thermostatic chamber 6I contracts the member i! by reason ofits inherent resiliency will restore the parts to their original relationship. Thus the embodiment of Fig. 2 operates in the same way, as heretofore described for the embodiment of Fig. 1.

The embodiment of Fig. 3 closely follows the embodiment of Fig. 2 except that the combined compensating thermostat and overrun provision is associated with the opposite end oi' the thermostat from that employed in Fig. 2 and also in As in the embodiment of Fig. 2, the casing Iii has an inlet the same a threaded aperture 53 in which is threadedly mounted a cup-shaped valve seatv member 54 providing a valve seat 55 that co-operates with valve member l0. Spring 5B is interposed between the bottom of the cup `and the valve member as in the embodiment of Fig. 2, and valve seat 55 may be adjusted by rotation of a stem 13 projecting through an aperture 1l and provided exteriorly of the casing with a stem portion 15 on which is mounted a sleeve 1I and knob 11 with associated elements, all as described with respect to the embodiment of Fig. 2. In this embodiment, valve member 90 is shown as integral with the end member 60 of the expansible and collapsible chamber Si having its peripheral wall formed by a corrugated bellowslike element and closed at its opposite end by the end member 03. However, it is to be understood that if preferred the valve member may be made separate from the end member $0 and suitably attached thereto. In this embodiment through a suitable aperture in the end member 63, more nearly as shown in Fig. 1, and communicates with any suitable bulb, as that indicated at 13 in Fig. i.

In this embodiment the bimetallic compensatlng thermostat and provision for overrun are associated with the mounting of the thermostatic chamber Il and take the form of a cup-shaped closure. member 9| threadedly mounted in the aperture 9.2 at the open end of the casing 50, with any suitable provision for assuring a hermetically sealed joint therebetween, and a spider-like resilient member 93 sprung into the depression or recess formed by peripheral flange 94. End member 63 is mounted in on said spider-like member 93 which reacts between said end member 63 and the closure member 0 i Again, as in iiuctuations of temperature around-and inside the casing 5i! eifect a relative diiferential expansion and contraction of the dissimilar metals of which the closure member 9| and the resilient member 93 are composed so that the location oi Mto the extraneous temperatures" li and outlet 52 and intermediate the preceding embodiments, the

flatten the spring-like element 93 so as to avoid injury to the thermostat. Upon contraction oi the thermostat thereafter, the inherent resiliency of the resilient member 93 will restore the parts to their normal relationship.

It will therefore be perceived that by the present invention a temperature regulator has been provided which employs means for compensating for uctuations in temperature other than that to which the temperature regulator is intended to respond and which at the same time avoids the objections and diiiiculties heretofore encountered where compensating thermostats have been employed, because the compensating provision is particularly simple in character, it at most requires no more than one additional member in the thermostatic system, and therefore the cost of production and of maintenance is maintained at a minimum. At the same time the compensating means is of -a character that renders it sensitively responsive to any iiuctuations of temperature occurring in or around the valve casing, and moreover the compensating means is of such a. character that by variations in the size and material of the associated members the desired compensating action can be nicely predetermined. f

Additionally the present invention provides for the inclusion of means to care for any overrun of the thermostat without the inclusion of additional elements, or ii the overrun provision is 'considered as a necessary adiunct, the compensating means is .provided without the addition of any element to the thermostatic system. In either event the combined -compensating means` and lprovision for absorbing overrun are of marked simplicity, whereby the inclusion thereof in the structure adds little to its cost and substantially nothing to its bulk, so that the combined Ifunctions are effected with the maximum simplicity and with high efiiciency as well as with the desired sensitiveness and precision to accomplish the desired ends.

While in the embodiments of Figs. l and 2 one of the members of the compensating thermostat' has, for purposes of exempliiication, been made integral with the valve member, and in the embodiment `of Fig. 3 integral with a Wall of the valve casing, it will be apparent that the valve member or the casing member may be a separate member from the recessed member of the bimetallic thermostat and suitably attached thereto,y

either unitarily or otherwise. Thus the members of the -bimetallic thermostat may be interposed at any. suitable location in the connection `between the expansible and collapsible thermostatic chamber and the valve member proper or between the thermostatic expansible and collapsible chamber and the casing on which it is mounted. II the recessed member of the Ibimetallic thermostat is made separate from the valve member proper or the casing wall, it may also be made of resilient construction so as to partake in the yielding of the bimetallic thermostat when said bimetallic thermostat functions as a means to absorb overrun of the thermostat. f While the embodiments of the invention illustrated on the drawings have been described with considerable particularlty it is to be expressly understood that the invention is not limitedthereto as the same may take a variety ont' expressions some of .which will `now be apparent to those Vskilled in the art, while changes may be made in the material, details of construction, arrangement oi' parts, etc., without departing from the spirit oi' this invention. Reference is therefore to be had to the appended claimsA for a definition oi' this invention.

What is claimed ist 1. In a temperature regulator of the type eniploying a thermostatically controlled valve mechanism which may be subjected to iluctuations od temperature at or adjacent to said valve mechanism, in combination with a. thermostat, a single means associated with the thermostat and constituting a combined compensating .thermostat for said temperature variations and the sole provision for absonbing overrun of the thermostat after the valve member has engaged its seat, said means comprising cooperating members which move relatively to each other both for compensating temperature variations and for absorbing overrun.

2. In a temperature regulator of the type employing a thermostatically controlled valve mechanism which may be subjected to i'iuctuationsot temperature at or adjacent to said valve mechanism, in combination with a thermostat, a single means associated with the thermostat and constituting a combined compensating thermostat for said temperature variations and the sole provision for absorbing overrun od' the thermostat after the. valve memberhas engaged its seat, said last named means including two members of dissimilar metal one of which is of resilient construction and which members cooperate -by differential expansion to vary the position of the valve member with respect to its seat and by relative yielding movement to absorb overrun of the thermostat. f

3. In a temperature regulator of the type employing a thermostatically controlled valve mechanism which may Ibe subjected to iiuctuations of temperature at or adjacent to said valve mechanism, in combination with a thermostat, a single means associated with said thermostat for compensating for said iluctuating temperatures and providing the sole means for absorbing overrun of the thermostat, said means including a recessed metallic member and a resilient member of dissimilar'metal sprung into said recess, said recessed member and said resilient member effecting relative movement of the valve member of said valve mechanism with respect to its seat by reason of diierential expansion and said resilient member yielding after said valve, member has engaged its seat tofabsorb overrun off said thermostat.

4. A temperature regulator according to claim temperature at or adjacent said valve mechanism,

Ain combination rwith a thermostaticaliy controlled valve mechanism a pair of coacting members ot dissimilar metal associated with said thermostatically controlled valve mechanism and at least one of said members being ci resilient construction, said members constituting a combined compensating thermostat dor said variations or temperature and the sole, means for absorbing overrun of said thermostat.

A temperature regulator according to claim 6 wherein said cooperating members oi dissimilar metal are interposed between the thermostat and the valve member proper.

8. A temperature regulator according to claim 6 wherein said cooperating members of dissimilar metal constitute a mounting for the thermostat.

il. In a temperature regulator including a thermostat having an expansible and .collapsible chamber, a valve member operatively connected to said chamber and a valve seat toward and away from which said valve member is moved by the ex on and contraction of said chamber, said valve member being formed of metal and having a depression at its rear race, and the operative connections between said chamber and valve member including a resilient member in the :form o! a bowed spring of metal .which is dissimilar to that or said valve member, said being engaged in said depression and constituting a thermostat with said valve member, said bowed spring being also yield'able with respect to said valve member to provide for relative movement between said chamber and said valve member.

10. In a temperature regulator including a ther-l mostat having an expansible and collapsible chamber, a valve member operatively connected to said chamber, .and a valve seat tow-ard and away from which said `valve member is moved by the expansion and contraction oi said chamber, and means mo nting said thermostat including a metallic member having a depression in its face .and a resilient member in the form oof a bowed spring engaged in said depression and constituting a thermostat with said metallic member, said bowed spring being also yieldable with respect to said metallic member to constitute 'a yielding mounting for said thermostat.

11. In a temperature regulator including a thermostat having an expansible and collapsible chamber, a valve member operatively connected to said chamber and a valve seat toward and away from which said valve member is moved by the expansion and contraction of said chamber, means associated with said thermostat and constituting a second thermostat for varying the pos ition or said valve member with respect to its seat including a metallic member having a depression in one of its iaces and a resilient memresilient member 1'? wherein said manually vances the valve seat ber engaged in said depression and constituting a bimetallic thermostat therewith, said second thermostat constituting the sole means for absorbing overrun of said iirst thermostat.

12. In a temperature regulator including a thermostat having an expansible and collapsible chamber, a valve member operatively connected to said chamber and a valve seat toward and away from which said valve member is moved by the expansion and contraction of said chamber, means associated with said thermostat and constituting a second thermostat, said means being composed o! two members of dissimilar metals at least one od which is of resilient construction, said members being disposed at right angles to the axis of said thermostat and said resilient member being bowed outwardly with respect to its cooperating member so that it may yield under overrun of said thermostat, and constituting the sole means for absorbing said overrun.

13. A temperature regulator according to claim 12 'wherein one of said members is integral with the valve member.

14. A temperature regulator according to claim 12 wherein said resilient member constitutes a 12 wherein said members are interposed between' the thermostat and the valve member proper.

16. A temperature regulator according to claim 12 wherein said members are interposed between the thermostat and its support.

17. In a temperature regulator including a thermostat having an yexpansi-ble and collapsible chamber, a valve member operatively connected to said chamber and a valve seat toward and away from which said valve member is moved by the expansion and contraction oi said chamber, cooperating members oi dissimilar metal associated with said thermostat and constituting a combined compensating thermostat and the sole provision for absorbing overrun, and means for manually moving the valve member and its seat relatively to each other independently o! the movements effected :by said iirst named thermostat and said .compensating means.

18. A temperature regulator according to claim adjustable means adtoward and away from said valve member.

19. A temperature regulator according to claim 17 wherein said manually adjustable means moves the thermostat and its associated valve member toward and away from its valve seat.

IUIS M. PUS 

